PMSM low voltage ride through based on Coordinated Control Strategy

Abstract

Based on the analysis of the operation characteristics of the fault of direct-drive permanent magnet wind turbine and the existing protection strategies, in order to improve the low-voltage operation capability of direct-drive permanent magnet wind turbine, a new coordinated control strategy for low-voltage crossing is proposed in this paper, which includes DC brake system control of unloading circuit, double second-order generalized integral phase-locked control, extracting positive and negative sequence of grid voltage and reactive power control on grid side. Based on the common three-phase symmetrical drop fault and asymmetrical fault caused by single grounding short circuit in power grid, PASCAD simulation experiment is conducted to verify the low voltage traversing ability of wind turbine.